Are the paths of electrons straight lines between successive collisions with the positive ions of metal in the presence of electric field?

Explanation

To answer the question, "Are the paths of electrons straight lines between successive collisions with the positive ions of metal in the presence of an electric field?", we will analyze the motion of electrons in two scenarios: without an electric field and with an electric field.

### Step-by-Step Solution:

1. **Understanding Electron Motion Without Electric Field**:
- In the absence of an electric field, electrons move freely and collide with positive ions in the metal lattice.
- When an electron is moving towards a positive ion, it will travel in a straight line until it collides with that ion.
- Therefore, in this scenario, the paths of electrons are indeed straight lines between successive collisions.
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